Definition
Adakite is an intermediate to felsic volcanic rock that has geochemical characteristics of magma which is said to be formed by partial melting of altered basalt that is subducted below volcanic arcs
Lamprophyre is uncommon igneous rocks primarily occurring as dikes, lopoliths, laccoliths, stocks and small intrusions
History
Origin
Adak, Aleutian Islands
-
Discoverer
Defant and Drummond
Unknown
Etymology
From Adak, Aleutian Islands
From Greek lampros bright and shining + porphureos purple
Class
Igneous Rocks
Igneous Rocks
Sub-Class
Durable Rock, Medium Hardness Rock
Durable Rock, Medium Hardness Rock
Family
Group
Volcanic
Plutonic
Other Categories
Fine Grained Rock, Medium Grained Rock, Opaque Rock
Coarse Grained Rock, Fine Grained Rock, Opaque Rock
Texture
Porphyritic
Porphyritic
Color
Black, Brown, Light to Dark Grey
Black, Bluish - Grey, Brown, Dark Greenish - Grey, Green, Grey
Maintenance
Less
Less
Durability
Durable
Durable
Water Resistant
✔
✘
✔
✘
Scratch Resistant
✔
✘
✔
✘
Stain Resistant
✔
✘
✔
✘
Wind Resistant
✔
✘
✔
✘
Acid Resistant
✔
✘
✔
✘
Appearance
Dull and Soft
Dull, Banded and Foilated
Architecture
Interior Uses
Decorative Aggregates, Floor Tiles, Homes, Hotels, Kitchens
Decorative Aggregates, Interior Decoration
Exterior Uses
As Building Stone, As Facing Stone, Office Buildings
As Building Stone, Office Buildings
Other Architectural Uses
Whetstones
Curbing
Industry
Construction Industry
As Dimension Stone, Cobblestones, Rail Track Ballast, Roadstone
As Dimension Stone, Cement Manufacture, for Road Aggregate, Making natural cement, Manufacture of Magnesium and Dolomite Refractories
Medical Industry
-
Taken as a Supplement for Calcium or Magnesium
Antiquity Uses
Monuments, Sculpture, Small Figurines
Artifacts, Monuments, Sculpture
Other Uses
Commercial Uses
Commemorative Tablets, Pottery, Used in aquariums
An Oil and Gas Reservoir, As a Feed Additive for Livestock, Gemstone, Metallurgical Flux, Production of Lime, Soil Conditioner, Source of Magnesia (MgO)
Types
Intermediate volcanic rock
Minette, Alnoite, Camptonite, Monchiquite, Fourchite, Vogesite, Appinite and Spessartite
Features
Has High structural resistance against erosion and climate, Host rock for Diamond, Very fine grained rock
Always found as volcanic pipes over deep continental crust, Host rock for Diamond, Is one of the oldest rock, Surfaces are often shiny
Archaeological Significance
Monuments
-
-
Famous Monuments
-
-
Sculpture
-
-
Famous Sculptures
-
-
Pictographs
-
-
Petroglyphs
-
-
Figurines
-
-
Fossils
Absent
Absent
Formation
Adakite rocks are formed when the hydrous fluids are released from minerals that break down in metamorphosed basalt, and rise into the mantle they initiate partial melting.
Lamprophyre formation takes place deep beneath the Earth’s surface at around 150 to 450 kilometres, and are erupted rapidly and violently.
Composition
Mineral Content
Olivine, Plagioclase, Pyroxene
Amphibole, Carbonate, Garnet, Micas, Olivine, Phlogopite, Pyroxene
Compound Content
Aluminium Oxide, MgO, Silicon Dioxide
Aluminium Oxide, NaCl, CaO, Iron(III) Oxide, FeO, Potassium Oxide, MgO, MnO, Sodium Oxide, Silicon Dioxide, Titanium Dioxide
Transformation
Metamorphism
✔
✘
✔
✘
Types of Metamorphism
Cataclastic Metamorphism, Contact Metamorphism, Impact Metamorphism, Regional Metamorphism
Cataclastic Metamorphism, Impact Metamorphism
Weathering
✔
✘
✔
✘
Types of Weathering
Chemical Weathering, Mechanical Weathering
Biological Weathering
Erosion
✔
✘
✔
✘
Types of Erosion
Coastal Erosion, Sea Erosion, Water Erosion
Chemical Erosion, Water Erosion, Wind Erosion
Physical Properties
Hardness
3-45-6
1
7
👆🏻
Grain Size
Fine to Medium Grained
Fine to Coarse Grained
Fracture
Conchoidal
Conchoidal
Streak
Bluish Black
White
Porosity
Less Porous
Very Less Porous
Luster
Grainy, Pearly and Vitreous
Subvitreous to Dull
Compressive Strength
200.00 N/mm2120.00 N/mm2
0.15
450
👆🏻
Cleavage
-
Conchoidal
Toughness
-
-
Specific Gravity
-99992.86-2.87
0
8.4
👆🏻
Transparency
Opaque
Translucent to Opaque
Density
-9999 g/cm32.95-2.96 g/cm3
0
1400
👆🏻
Thermal Properties
Specific Heat Capacity
0.84 kJ/Kg K0.84 kJ/Kg K
0.14
3.2
👆🏻
Resistance
Heat Resistant, Pressure Resistant, Wear Resistant
Heat Resistant, Impact Resistant
Deposits in Eastern Continents
Asia
India, Russia
Russia
Africa
Ethiopia, Somalia, South Africa
Angola, Botswana, Cameroon, Ethiopia, South Africa
Europe
Iceland
England, Hungary, Iceland, United Kingdom
Others
-
Antarctica, Greenland
Deposits in Western Continents
North America
Canada, USA
Canada, Mexico, USA
South America
Brazil
Argentina, Colombia, Ecuador
Deposits in Oceania Continent
Australia
-
New South Wales, New Zealand, Queensland, South Australia, Western Australia